Try the Table of Contents. Dunno which publisher's book you are using and sadly, some of the republishers don't take advantage of the fact that government regulations are laid out by subject. Title, Chapter, SubChapter, Part, Subpart, Regulation. Each Subpart represents a distinct subject.
Part 91 is our basic operating regulations, Subpart B in 91 arE the flight rules. Even within the Subparts, the regs are grouped together by subject, general, VFR, IFR in seqyence.
No one had ever shown him that and it made all the difference to him. Basically, he ended up tabbing the ToC and drawing blocks around the groupings.